Patent GB-1493822-A (GB)
Title: Composite polymer-fabric product
IPC: D06N3/00
Filed: 1974-09-19
Abstract: 1493822 Laminates INMONT CORP 19 Sept 1975 [19 Sept 1973 30 May 1974] 21839/77 Divided out of 1493821 Heading B5N A laminate consists essentially of (a) a layer of permeable fabric made of interlaced fibre yarns and having a flat upper face, the interlaced yarn structure of the fabric having a drape stiffness of less than 2 inches; (b) a layer of water vapour permeable microporous elastomeric polymer having a density in the range of 0À3 to 0À4 g/cm<SP>3</SP> and a thickness of 0À3 to 0À8 mm.; (c) an elastomeric adhesive bonding the lower face of the microporous layer to the upper face of the fabric, the adhesive being in contact with the upper surface of the fabric which is substantially non-impregnated by the adhesive. The laminate may be made by adhering one face of a sheet of preformed microporous polymer to a temporary backer, and adhering the fabric to the other face thereof, the fabric being preferably adhered by applying a thin deposit of adhesive to the other face of the sheet and, when the adhesive is tacky, pressing the fabric thereagainst to mould the adhesive to the fabric surface while keeping the fabric substantially non-impregnated and non- stiffened by the adhesive, setting the adhesive and stripping off the backer, the adhesive being one which sets from a tacky condition to a non- tacky elastomeric condition; the adhesive being preferably applied to the sheet of microporous polymer as a solution in a volatile solvent which is a swelling agent for the polymer, the sheet of microporous polymer optionally containing a coagulant for the solution in its micropores. In a preferred embodiment, the microporous layer has a skin on the surface thereof remote from the fabric, the skin being formed wholly or in part by coating a solution of the skin material on to a temporary support, e.g. a release paper, placing a microporous sheet on the tacky coating and removing the solvent therefrom; alternatively, the microporous layer may comprise two or more sub-layers of differing density. Specified materials for the microporous sheet are polyurethane and polyvinyl chloride. The fabric is preferably woven or knitted and may be formed of cotton, polyester, e.g. polyethylene terephthalate, nylon, e.g. nylon-6 or nylon-6,6, polyolefin, e.g. polypropylene, acrylic, e.g. polyacrylonitrile, rayon or a blend thereof. The fabric may have an unnapped surface bonded to the microporous layer, the other surface of the fabric being unnapped or, preferably, having a nap of fibres teased from the yarns thereof and bonded together. The temporary backer, which may be used as a support for the formation of the microporous layer may be of release paper. A specified adhesive comprises an hydroxyl terminated polyester or polyether as one component and a polyisocyanate as the other components, one or both of which are supplied in solution, being mixed just before use, optionally with the addition of a catalyst. The bonding agent for the nap fibres may be a latex of a homo- or co-polymer of ethyl acrylate or a latex of a diene homo- or co-polymer, e.g. a rubbery butadiene-acrylonitrile copolymer; alternatively, a solution of a two-component elastomeric polyurethane may be used. The products of the invention may be used as a substitute for leather.